294 On the Physical Geology of the United States, §c. 
mountains, mountain chains and continents, and produce all the 
phenomena of contortion, wrinkling, folding and crushing of the 
strata, that are so strikingly exhibited in = eastern parts of the 
United States. 
That both the causes above stated have acted in times past, 
and will continue in time to come, can scarcely be doubted. 
The phenomena of both these causes necessarily follow from the 
refrigeration of the globe. Subsidence of parts of the earth’s crust 
may, and probably have caused extensive elevation of others; 
but we know of no other cause that could produce this effect, 
except the fractured crust permitting water to penetrate to the 
heated interior of the earth, to generate steam sufficient in ten- 
sion and quantity to effect the results observed; and we know 
not how the crust could be fractured except by een and 
by collapse upon the contracted nucleus. 
That some portions of the crust of the globe have been suc- 
cessively elevated and depressed, is beyond all doubt. Numer- 
ous instances have been observed during the historical epoch,* but 
the geological evidences of similar facts on a large scale, are as 
strong as if they had come under the direct observation of man. 
That the elevation of one part was accompanied in times past 
by depression in others is probable theoretically, and we know 
that such facts have occurred paroxysmally during the historical 
era, as in the case of the Ullah Bund. Similar effects are now in 
progress secularly, as the coast of Sweden, which is gradually 
rising, and has been for a long period; the coast of Greenland, 
* A few examples may be adduced for illustration. 
ist. An island in the Mississippi, and a large extent of the swamp near New 
Madrid, sunk during an earthquake in the year 1811. The Mississippi flows over the 
former site of the island, and the sunken portion of the swamp is now a lake. 
2d. In the year 1819, a tract of land of about two thousand square miles near the 
mouth of the Indus at Sindrea sunk below the level of the sea, and an adjoining 
tract fifty miles long, called the Ullah Bund, was raised about ten feet above its 
former level. 
3d. In the year 1692, the town of Port Royal in Jamaica sunk during an earth- 
quake. The ships in the harbor floated from their anchorage and drifted over the . 
site of the town, which remains permanently submerged. The part of the town 
where the quay was located sunk several hundred feet. 
4th. In 1638, the town of Euphemia in Calabria sunk during an earthquake. 
A lake occupies its site. 
Sth. The coast of Chili in South America was elevated suddenly during an 
earthquake in 1822, over an extent of two hundred miles in length and forty or 
fifty miles in breadth into the interior. At one place some distance back from the 
